I think a confident rider can be rattled by things their horse (the horse they are riding) does but when they are rattled, they just keep going. They don't just give up because something is a little scary. I think there's absolutely nothing wrong with being scared, you just have to keep going anyway.
Being a confident rider means that you act like you know what you're about and you think quickly on your feet so you know what you're about. You project an appearance of competence, even if you don't feel competent. You have a plan for each ride but are willing to change that depending on the circumstances and not get flustered by the change.
And, you can ride a variety of different horses and go with it, solving problems as they come up and not getting frustrated or getting scared enough that you just can't go on. A little fear is ok, it means you're human, but excessive fear is unnecessary.
Fabio - 13 year old Arabian/Lipizzan gelding
Rest peacefully, Lacey.